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Simulation of CO2 Storage using a Parameterization Method for Essential Trapping physics: FluidFlower Benchmark Study

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arXiv 2023年

作者： Wang, Yuhang Zhang, Ziliang Vuik, Cornelis Hajibeygi, Hadi School of Environmental Studies China University of Geosciences Wuhan430078 China Faculty of Electrical Engineering Mathematics and Computer Science Department of Applied Mathematics Delft University of Technology Delft2628XE Netherlands Faculty of Civil Engineering and Geosciences Department of Geoscience and Engineering Delft University of Technology Delft2628CV Netherlands

An efficient compositional framework is developed for simulation of CO2 storage in saline aquifers during a full-cycle injection, migration and post-migration processes. Essential trapping mechanisms, including structural, dissolution, and residual trapping, which operate at different time scales are accurately captured in the presented unified framework. In particular, a parameterization method is proposed to efficiently describe the relevant physical processes. The proposed framework is validated by comparing the dynamics of gravity-induced convective transport with that reported in the literature. Results show good agreement for both the characteristics of descending fingers and the associated dissolution rate. The developed simulator is then applied to study the FluidFlower benchmark model. An experimental setup with heterogeneous geological layers is discretized into a two-dimensional computational domain where numerical simulation is performed. Impacts of hysteresis and the diffusion of CO2 in liquid phase on the migration and trapping of CO2 plume are investigated. Inclusion of the hysteresis effect does not affect plume migration in this benchmark model, whereas diffusion plays an important role in promoting convective mixing. This work casts a promising approach to predict the migration of the CO2 plume, and to assess the amount of trapping from different mechanisms for long-term CO2 storage. © 2023, CC BY-NC-ND.

关键词： Porous materials

Time-domain Li-ion Battery Modeling under Staircase Charging and Discharging

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Time-domain Li-ion Battery Modeling under Staircase Charging...

2021 International Conference on Microelectronics, ICM 2021

作者： Abdelhafiz, Shahenda M. Abdelaty, A.M. Fouda, M.E. Radwan, A.G. Giza Egypt Fayoum University Faculty of Engineering Engineering Mathematics and Physics Dept. Egypt Cairo University Faculty of Engineering Engineering Mathematics and Physics Dept. Egypt University of California-Irvine Electrical Engineering and Computer Science Dept. Irvine United States School of Engineering and Applied Sciences Nile University Giza Egypt

ISBN: (纸本)9781665408394

Parameter identification of Li-ion battery models is important for efficiently charge and discharge the most widely used energy storage devices. In this work, we propose a simplified battery model with a parameter identification method for time-domain charging and discharging. Staircase PotentioElectrochemical Impedance Spectroscopy technique (SPEIS) is chosen to characterize the batteries during charging and discharging cycles at different voltage steps values. Marine Predator Algorithm (MPA) is used to identify the proposed model parameters on two commercial Li-ion coin-shaped batteries. The proposed model shows very good matching with the experiments with absolute current error less than 10 4. Hence, the proposed model can be used for real-time applications to predict the battery's behavior under different operating conditions. © 2021 IEEE.

关键词： Lithium-ion batteries

DYNAMICS ON THE PATH SPACE OF GENERALIZED BRATTELI DIAGRAMS

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arXiv 2022年

作者： Bezuglyi, Sergey Jorgensen, Palle E.T. Karpel, Olena Sanadhya, Shrey Department of Mathematics University of Iowa Iowa City United States Faculty of Applied Mathematics AGH University of Science and Technology Krakow Poland B. Verkin Institute for Low Temperature Physics and Engineering Kharkiv Ukraine Department of Mathematics Ben-Gurion University of the Negev Beersheba Israel

Bratteli-Vershik models have been very successfully applied to the study of various dynamical systems, in particular, in Cantor dynamics. In this paper, we study dynamics on the path spaces of generalized Bratteli diagrams that form models for non-compact Borel dynamical systems. Generalized Bratteli diagrams have countably infinite many vertices at each level, thus the corresponding incidence matrices are also countably infinite. We emphasize differences (and similarities) between generalized and classical Bratteli diagrams. Our main results: (i) We utilize Perron-Frobenius theory for countably infinite matrices to establish criteria for the existence and uniqueness of tail-invariant path-space measures (both probability and σ-finite). (ii) We provide criteria for the topological transitivity of the tail equivalence relation. (iii) We describe classes of stationary generalized Bratteli diagrams (hence Borel dynamical systems) that: (a) do not support a probability tail-invariant measure, (b) do not admit a continuous Vershik map, (c) are not uniquely ergodic with respect to the tail equivalence relation. (iv) We provide an application of the theory of stochastic matrices to analyze diagrams with positive recurrent incidence *** Codes 37A05, 37B05, 37A40, 54H05, 05C60 © 2022, CC BY.

关键词： Dynamical systems

Enhanced Superconductivity in SrTiO3-based Interfaces via Amorphous Al2O3 Capping

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arXiv 2024年

作者： Silber, I. Azulay, A. Basha, A. Ketchker, D. Baskin, M. Yagoda, A. Kornblum, L. Kohn, A. Dagan, Y. School of Physics and Astronomy Tel-Aviv University Tel Aviv69978 Israel Department of Materials Science and Engineering The Iby and Aladar Fleischman Faculty of Engineering Tel-Aviv University Tel Aviv6997801 Israel The Andrew and Erna Viterbi Faculty of Electrical and Computer Engineering Technion – Israel Institute of Technology Haifa32000-03 Israel

Oxide interfaces feature unique two-dimensional (2D) electronic systems with diverse electronic properties such as tunable spin-orbit interaction and superconductivity. Conductivity emerges in these interfaces when the thickness of an epitaxial polar layer surpasses a critical value, leading to charge transfer to the interface. Here, we show that depositing amorphous alumina on top of the polar oxide can reduce the critical thickness and enhance the superconducting properties for the (111) and the (100) SrTiO3-based interfaces. A detailed transmission electron microscopy analysis reveals that the enhancement of the superconducting properties is linked to the expansion of the LaAlO3 lattice in a direction perpendicular to the interface. We propose that the increase in the superconducting critical temperature, Tc, is a result of epitaxial strain. Copyright © 2024, The Authors. All rights reserved.

关键词： Electronic properties

On b-acyclic chromatic number of a graph

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arXiv 2022年

作者： Anholcer, Marcin Cichacz, Sylwia Peterin, Iztok Poznań University of Economics and Business Institute of Informatics and Quantitative Economy Al.Niepodleglości 10 Poznań61-875 Poland AGH University of Science and Technology Faculty of Applied Mathematics Al. Mickiewicza 30 Kraków30-059 Poland University of Maribor Faculty of Electrical Engineering and Computer Science Koroška 46 Maribor2000 Slovenia

Let G be a graph. We introduce the acyclic b-chromatic number of G as an analogue to the b-chromatic number of G. An acyclic coloring of a graph G is a map c: V (G) → {1,..., k} such that c(u) ≠ c(v) for any uv ∈ E(G) and the induced subgraph on vertices of any two colors i, j ∈ {1,..., k} induces a forest. On the set of all acyclic colorings of G we define a relation whose transitive closure is a strict partial order. The minimum cardinality of its minimal element is then the acyclic chromatic number A(G) of G and the maximum cardinality of its minimal element is the acyclic b-chromatic number Ab(G) of G. We present several properties of Ab(G). In particular, we derive Ab(G) for several known graph families, derive some bounds for Ab(G), compare Ab(G) with some other parameters and generalize some influential tools from b-colorings to acyclic *** Codes 05C15 © 2022, CC BY-NC-ND.

关键词： Coloring

Approximation algorithms for steiner tree based on star contractions: A unified view 15

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Approximation algorithms for steiner tree based on star cont...

15th International Symposium on Parameterized and Exact Computation, IPEC 2020

作者： Hušek, Radek Knop, Dušan Masařík, Tomáš Computer Science Institute of Charles University Faculty of Mathematics and Physics Charles University Prague Czech Republic Department of Theoretical Computer Science Faculty of Information Technology Czech Technical University in Prague Czech Republic Faculty of Mathematics Informatics and Mechanics University of Warsaw Poland Department of Applied Mathematics Faculty of Mathematics and Physics Charles University Czech Republic

ISBN: (纸本)9783959771726

In the Steiner Tree problem, we are given an edge-weighted undirected graph G = (V, E) and a set of terminals R ⊆ V . The task is to find a connected subgraph of G containing R and minimizing the sum of weights of its edges. Steiner Tree is well known to be NP-complete and is undoubtedly one of the most studied problems in (applied) computer science. We observe that many approximation algorithms for Steiner Tree follow a similar scheme (meta-algorithm) and perform (exhaustively) a similar routine which we call star contraction. Here, by a star contraction, we mean finding a star-like subgraph in (the metric closure of) the input graph minimizing the ratio of its weight to the number of contained terminals minus one;and contract. It is not hard to see that the well-known MST-approximation seeks the best star to contract among those containing two terminals only. Zelikovsky’s approximation algorithm follows a similar workflow, finding the best star among those containing three terminals. We perform an empirical study of star contractions with the relaxed condition on the number of terminals in each star contraction motivated by a recent result of Dvořák et al. [Parameterized Approximation Schemes for Steiner Trees with Small Number of Steiner Vertices, STACS 2018]. Furthermore, we propose two improvements of Zelikovsky’s 11/6-approximation algorithm and we empirically confirm that the quality of the solution returned by any of these is better than the one returned by the former algorithm. However, such an improvement is exchanged for a slower running time (up to a multiplicative factor of the number of terminals). © Radek Hušek, Dušan Knop, and Tomáš Masařík;licensed under Creative Commons License CC-BY

关键词： Stars

Propagation Characteristics of Partial Discharges in an Oil-Filled Power Transformer

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Propagation Characteristics of Partial Discharges in an Oil-...

Compatibility in Power Electronics (CPE)

作者： Sayed Mohammad Kameli Shady S. Refaat Ali Ghrayeb Haitham Abu-Rub Jarosław Guziński Electrical and Computer Engineering Texas A&M University at Qatar Doha Qatar Department of Engineering School of Physics Engineering and Computer Science University of Hertfordshire Electrical and Control Engineering Faculty Gdansk University of Technology ul. Gabriela Narutowicza 11/12 Gdańsk Poland

Power transformers are among the most important assets in the power transmission and distribution grid. However, they suffer from degradation and possible faults causing major electrical and financial losses. Partial discharges (PDs) are used to identify the insulation health status and their degradation level. PDs are incipient, low-magnitude faults caused by localized dielectric breakdown. Those activities emit signals in many forms, including electrical, chemical, acoustic, electromagnetic, and optical, facilitating various detection methods. This paper provides a theoretical basis for the condition evaluation of an oil-filled power transformer and clarifies the relationship between the operating voltage, void location, and electric-field intensity within the void. This was achieved by investigating the propagation characteristics of partial discharge signals in an oil-filled power transformer using a 3D finite element method (FEM) based simulation. Moreover, the characterization of simulated PD sources at different positions is investigated in this paper. The simulation results are curried out to show that air voids near the windings are subject to greatest peak electric field intensity.

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Nanomaterial-based biosorbents:Adsorbent for efficient removal of selected organic pollutants from industrial wastewater

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Emerging Contaminants 2022年第1期8卷 46-58页

作者： Hussein.K.Okoro Sadanand Pandey Clement O.Ogunkunle Catherine J.Ngila C.Zvinowanda Ismaila Jimoh Isiaka A.Lawal Muyiwa M.Orosun Adewale George Adeniyi Analytical-Environmental Research Group Department of Industrial ChemistryFaculty of Physical SciencesP.M.B.1515University of IlorinPostal Code 240003IlorinNigeria Department of Chemistry College of Natural ScienceYeungnam University280 Daehak-RoGyeongsanGyeongbuk38541Republic of Korea Environmental Botany Unit Department of Plant BiologyUniversity of IlorinIlorinNigeria Analytical-Environmental and Membrane Nanotechnology Research Group Department of Chemical SciencesFaculty of ScienceUniversity of JohannesburgP.O.Box 17011Doornfontein2028JohannesburgSouth Africa Psychometrics Department JAMBNigeria Chemistry Department Faculty of Applied and Computer ScienceVaal University of Technology1900VanderbijlparkSouth Africa Health and Environmental Physics Research Group Physics DepartmentUniversity of IlorinIlorinNigeria The African Academy of Sciences P.O.Box 24916-00502 NairobiKenya Physical Address:8 Miotoni LaneKarenNairobiKenya Department of Chemical Engineering Faculty of EngineeringUniversity of IlorinPMB1515IlorinNigeria

The contamination of the environment by organic pollutants is a major risk factor,particularly for developing *** organic pollutants(SOPs)like the phenolic compounds,polyaromatic hydrocarbons(PAHs),pesticides,and herbicides pose serious environmental and health issues owing to their toxic characteristics and poor *** from their potential mutagenicity,carcinogenicity,tetragenicity and high body accumulation,these pollutants have become an increase concern *** is a promising alternative strategy for removing organic pollutants during water purification *** have several advantages such as simplicity of operation,good sorption capacity,high recoverability and *** a result,the focus and novelty of this review is on recent trends in the use of biosorbents,with a particular emphasis on the removal of SOPs from *** also cover use of bacteria biosorbents,fungal,algae and chitosan/chitin *** from that,we have also reviewed various classes of SOPs,their levels in the environment,classification and available characteristics techniques suitable for the adsorption experiments of these nanocomposites *** addition,we have provided comprehensive explanations and conclusions on possible future application of biosorbents and the mechanism of adsorption of these materials for removal of these SOPs from wastewater during water purification processes.

关键词： Biosorbents Adsorption Organic pollutants Biosorption Wastewater

Process of Magnetization in Strong Magnetic Fields of Amorphous Fe-Based Alloys

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Process of Magnetization in Strong Magnetic Fields of Amorph...

作者： Stambula, S. Nabialeka, M. Paszta, P. Nabialek, M.M. Pietrusiewicz, P. Somidin, F. Jez, B. Department of Physics Faculty of Production Engineering and Materials Technology Czestochowa University of Technology al. Armii Krajowej 19 Częstochowa42-200 Poland Department of Technology and Automation Faculty of Mechanical Engineering and Computer Science Czestochowa University of Technology al. Armii Krajowej 19c Częstochowa42-200 Poland Center of Excellence Geopolymer and Green Technology Universiti Malaysia Perlis Taman Muhibbah Perlis Arau02600 Malaysia

Amorphous alloys exhibit a similar course of the magnetization process as crystalline materials. This means that there is also a domain structure in their volume, the changes of which describe the magnetization process well. These defects are a kind of inhomogeneity of the material structure and become an area where there are disturbances in the alignment of spins in relation to the intensity of the external magnetic field. These disturbances are the reason for the change in the course of the M-H curve. Using the theory developed by H. Kronmüller, it is possible to study the process of magnetization of amorphous ferromagnetic alloys in strong magnetic fields. The work analyzes the change in the process of magnetization of amorphous iron alloys along with the change in their chemical composition. © 2025 Polska Akademia Nauk. All rights reserved.

关键词： Amorphous alloys